Closures and Higher-Order Functions

Closures and Higher-Order Functions

In this lesson — part of Advanced Features — you'll learn closures and higher-order functions in MATLAB and why it matters in real work.

Why it matters

Functions that take or return functions unlock concise, composable code.

Key ideas

• Functions as values
• map / filter / reduce
• Callbacks
• Composition

In practice

Here's how it looks in idiomatic MATLAB:

nums = 1:5;
sq = arrayfun(@(x) x^2, nums);        % map over array -> [1 4 9 16 25]
C = cellfun(@upper, {'a','b'}, ...
            'UniformOutput', false);  % needed for non-scalar output
tot = sum(nums(arrayfun(@(x) mod(x,2)==0, nums)));  % filter+reduce

MATLAB note: arrayfun/cellfun require 'UniformOutput', false whenever the per-element result isn't a scalar, otherwise MATLAB errors trying to pack results into a numeric array.

Try it yourself

Exercise: In MATLAB, use map and filter to get the squares of the even numbers.

Recap

You now understand closures and higher-order functions and can apply it in MATLAB. Mark this lesson complete and continue to the next one.